Means for controlling dust in the screening of dust-laden material



Aug. 14, 1945. w. J. PARKS 2,332,252

MEANS FOR CONTROLLING DUST IN THE SCREENING OF DUST-LADEN MATERIAL Filed Dec. 9, 1941 5 Sheets-Sheet l INVENTOR. WALTER J. PARKS.

ATTORNEYS.

Au 14, 1945. A KS 3 2,382,252

MEANS FOR CONTROLLING DUS T IN THE SCREENING OF DUS T-LADEN MATERIAL Filed Dec. 9, 1941 5 Sheets-Sheet 2 INVENTOR. WALTER 4.? PARKS ATTORNEYS WKMM/M w. J. PARKS 2,382,252

MEANS FOR CONTROLLING DUST IN THE SCREENING OF DUST-LADEN MATERIAL Aug. 14, 1945.

Filed Dec. 9

m S R F vm ms M K R Q 1 m U J A R J d wv A N N 3 N w 2 l I I I I I l l I l I l l l l I l II I ll I l i l l l l l I l I. I A v l w 1 1| 0 0 m o w "@J a o a m a v Hu H min lfl HU I H H I H h l hl h h H HHI HIH 'HHI I H I I I HH HUN l lHdl l WlH l i l l l l /f m BY f ZZL

Aug. w PARKS MEANS FOR CONTROLLING DUST IN THE SCREENING OF DUSTLADEN MATERIAL Filed Dec. 9, 1941 5 Sheets-Sheet 4 INVENTOR. WALTER J PARKS ATTORNEYS A g- 5 WVJ. PARKS 2,382,2 2

MEANS FOR CONTROLLING DUST IN THE SCREENING OF DUST-LADEN MATERIAL Filed Dec. 9, 1941 5 SheetsSheet 5 INVENTOR. WALTER J PARKS ATTORNEYS.

Y ible connections of canvas pr rubber "were re -5* Figl'fi is"afragmentary ansver ficm Patented Aug. 14, 1945 i uNlTEofsTA-TES"; PATENT. OFFIC MEANS FOR CONTROLLING DUST IN-THE SCREENING F DUST-LADENMATERIAL Walter J. Park's, Cleveland Heights, 'Ohio, assign! to The W. ,s Tylericompany, Clevelandl qhio; a corporation of qhio l Application-Decemberl),1941, SerialNo. 422.256-

1 ll f1 n solates, titer. 209-370) This invention relates, as indicated, to means or openings' withthe screen bodyjwhichwopen-J for controlling dust in the screening of dustings can be varied in size. .1 v v laden materials. l l Otherobjects'and advantages of theinvention" Various attempts have heretofore been made will be apparent durlng the course of thetiolto combat the problem of controlling the spread- 1'; "lowing. description. l v .I ing of dust in the screening of dust-laden ma Intheaccompanying drawings, forming apart terials, so as to eliminate, asfar as possible, the of this specificationland in whichlike 'numeralsv hazards to the health of laborers and others are'employed to' designate'likeparts tl'irough'oul'.v Working about screening apparatus employed in the same, :3 l screening such materials. fort. Fig."1isa frontend elevation of ascreening It has been common practice in the screening"? machine having incorporated therein the novel art to completely enclose vibrating screen bodies enclosure air sealof the present invention? by attaching cover plates rigidly to the same, but Fig.2'is"a side elevation of the aforesaid creen: except on small and light units, this ha s'I Ot ing machine; proven satisfactory because (1) "the weight-oi l- Fig. 3 is a longitudinal brokenbross-se'ctional" the covers and thenecessary stiffenerstl'i'ereon View of the machine taken br'1theline 3-f-3 oi constituted an additional load'on thebearings' Fig, 1; v and materially reduced the life expectancyoi the Fig. 4 is a fragmentary longitudinal cros N same, (2) the attachment of the covers in such tional view, throughthe'upper portionbf the feed f a manner as to make the joints' 'dusttight re-'20'end of the apparatus; takenon theline 4 4 of"; quired a multiplicity ofbolts or other cover se Fig. 1; 4 i j curing devices which increased, to an objection Fig. 5'is afragmentary 'l'iorizo'ntalf cros se able point, the-time required to change 'scr'ee' 'tional view, through theapparatus; taken th cloths within the enclosedbody, andf (3-'fl line 5--5 of Fig.2;" 1 l quired at the feed inlet, oversize discharge and tion'al view throughfjt fines outlet pointsand itwas difficult to make line 6-'60f Fig; 21 'Q he apparatus taken ord th such connections permanently dust-tight due to Fig. 7 'is a view si the vibration looseningQthe connections and the a modified firmer turef 1' I Q rapid deterioration of themateriall 80 Fig'fs is ane similar to Fig. 5,

The present invention has as its primary 010- m difi d form of 'structureii' ject the provision of amethod of and means for gg is ",i i fii t Fi jle, b ghc'win controlling dust in thescreening of dust-laden a m difidj m bf ti t fj' materials, which are freefrom all of the afore- Fig m s n a y mv fi d disadvantages and which are l ing a modification in tthe nieansforise 1 6w fective in reducing '0 a m, h iQ e cover plates to the air. sealenclosure and r hazards to the health of laborers and others i Fig 11 i g 'r g dfinwestern1m; working about screening apparatus employed in i Y screemng 1 t T novei enclosure a e;entr e presen Another, obJect of the nvention is to provide ,40 ihvention maybeinqorporafiedin Markus 'e dixftc fiife nfif ififii tg fi ofi screens, but pur'lwslesl illustration, 5 yrating parts ofthe screening machine, so as to shown as embodled mfigyratqyscregl} i 7 be free from the vibrating or' gyratory'movement giigzfi i g sz dlslclqisedm 3 5. of the screen body. ,Th s'prmits" the use of I cover plates of minimum thickness, the use of a Such scregn 98 2 2?zjgffi i g g ggi relatively small number of cover plate securing Suppor mg as l devices, and the use of rigid air remoVal connections, which can be made dust-tight.

Another object of the invention is to provide an air sea] enclosure consisting of a relatively to the screen body. Thet base. or ;fran1e; in thi m-case, consistsof a pair of transversely spaced base w; rails l, inthe form of IrbeamsrconnectedJoya 13; light operrfranie, permitting ready access to the' plurality of longltudinallylspaced I.-'beams:\2;:the=q: screen cloth tensioning bolts. l r base rails havingsecureuw-to therends1thereof"i A further object of the inventionisto provide. plates 3, to which are-secured-vcablesfl; w'vhe'rebym an air seal enclosure forming an -passageways thebaseframe maybe flexiblysuspendedcprefn and'rneansfor impartingna vgyratcry movernent i and; thezadjacent :edgeiofthewi-bratingside plate erably in an inclined position, from any desired superstructure (not shown).

The screen body, in this case, which is disposed within the base frame, comprises a pair of transversely spaced side plates 4 and 5, which are disposed in planes parallel with but spaced inwardly of the base rail s, and screens 6 andJLwhicmextend transyerselyuor said':side plates-frthe upper screen 6 being of coarser mesh than the lower screen I. The screen body is resiliently mounted on the base rails, as by means of resilient supports generally indicated at 8,.and-'11sprovidedumi; with a transversely extending Sha'ft'S'jE which-1e; tends through the side platesand. upon, rotation. of which a gyratory movementisimparteditoathel screen body. The shaft 9 is supported'at its ends in gyratory supporting bodies I0; which, in turn, are resiliently mounted on the base-rails zas by. m llneans of resilient supports generally indicated at. r.

Thehovel enclosure or-air seal willznow bedem. scribed in detail. I v

'lheienclosure, in its, preferredrform;consistsxof;

a rectangular frame;-mountedriadjacentrto eachsw side plate, on the base frame of thetmachinezso. that sthere are iormed' '-'r"estricte,d oopenings: or clearances,- :betWeen each". member 0f: the i trame of the machine. Specifically this rectangular framerconsists or four uprightsans-les. 42. andrl3 of Fig: 2 beingadjacentztothetends ofi-side: plate! F on one sidezof.therscreen'sbodm and-A4 andnli: of Fig. 5,:being 'adjacentito the.-errdsneifithe othersidev plate 5 on the opposite side of the bodm-atwo-lon gitudinallyextending! angles; 2H5 and-11H, mounted on :.top ofv said uprights-and. running talon n and 5": adjacent to, the top of the side plates 4 and .519 respectively andetwmbottom -members running from the bottom. of. the. uprights :parallel and ad jacent to;thejbottomaoi the side -.plates hand, 5..- 430 -These bottom members are represented by thenu angler52 in Fig: 9,;orin amodifiediorm-by the bentzangle 46; andmibberstrip 45.0frFig21-6; u.

Mounted on the members l6 and; I I) are suitable-4' covenplates 20; whicharerremovablarashv' means of handles; to permit; accessitosthe screenrbodyt- 25- and a feed plate 22, the latter beinglmounted on 9. rearward extension; 01?- thezmembers t6 and .l 1;; and having an opening-Z3;thereimforrtheieeding of the materials to be-screenedw The. cover plates may be secured to the members 4.6 anddlin-the manner. ,shown in Fig. .6,. thatlisl by means-.ot bolts 24 pivoted to pins...26 mountedin brackets 21 whichare. boltedto the member's l5 and .11. The. bolts '24 extend. through slotted.openings in the'edges' oi theicov'er plates 20, andnuts28. are secured to the .bolts above. these openings. This provides a ready means of securinggthe cover plates to the enclosure or air seal, a'nd permits easy removal of such plates;when necessary. 1

Secured, in a removablemanner, to thejangles l3 and I 4 'isa discharge plate-29 (Fig. 3) ,having 1 opening'sy3l1 and 3| therein-for the"dischar'ge' -01" thesizedmaterials from the upper; and ;lower screens respectively.

At the rear-of the enclosure-or air-seal--is a chamber P '(Figs. 4=and- 5); which maybe termed a plenum"chamberisince'air sucked' through the spaces between the screen-body and th'e'enclosure J is drawn into this *space' before being removed- '70 from-the screen: Thisplenum chamberiisformed by means of triangularjshapedsidelplates 32: and :1; 33 which are securedrtotheruprightszlr! and. I5; and-Ia back plate, whichiiszsecuredyas by meansm of thel-iangles :35 t0 saides'idei plates-.wziThe :spacszJii between the upper end of the back plate 35 and the feed plate 22 is filled by an angle cross-member 36, which is bolted to said feed plate (Fig. 4). A conduit 31 for removal of air from the plenum chamber is secured to the back 35, as best shown in Fig. 3.

The. enclosurewhich is thus provided may be rigidly-connected to the base framerby means of bolts and rivets, but is preferably mounted in the following manner. The discharge end section is constructed as a rigid upright unit consisting of the'uprightxanglesqwand l4 and the discharge plate. 29 (Figl-"B-lwhich is fastened to the dischargeend ,cross bearnj by means of the hinged connection 8. (.Figixl} and held in place by means of the hDElBfiflB. and 19 (Fig. 2) attached to the body and the base frame respectively in such a mannext thatrwhenithef'bolts joining the two are removed the upright unit can be swung outwardly away from the screen body. The feed end section is also constructed as-a unit consisting of the ,up-

right-.;angles;-|,2 and: |5,'.the' triangularshaped rigid hnitwonsisting; of: the longitudinalrangles l6 a andat'l.the-.feed plate.- 2.2-, the crossmernber 36 and-:othen cross members as required --but' not in- ;cluding the detachable cover plates which bolt-to flangedqmembers on top of the .upright .angles.- This construction permits then-rapid y dis-assembly of the enclosure it forany reasomas for exam ple thescreen body, is-tobe removednrom the base. frame. as ayllnitg'COmDIEtBflOCBSS-tO thE screen bodyAs-necessary; :Jn this case the flanged-joint connecting eithenendpfi the top section to its upri ti u p rt an--beun o1ted .and ,the .comfplete unit .Qf thestop section and'the other .end section canibe, swung. backout otthe way,;or the con-..

nectlons at both ends Can be unfastened andeach endsection swung independently .away..from.the

screen.-.-.body.. This; eliminates. the .necessity. of

unboltingreachseparate partrofleachunit and results in a, very. importantv ,saving of time .when

such-an operationisnecessary I The. material passing through the-Jbottom deck of the. yibratinetsq een body dlropsjthrough .fihe

operiingenclosed, byjthe gmembers .2 and 45 of Fig. 3. This opening,,if.-not, restricted, .would necessitate the hahdlingofl an excessive amount of air .to maintain flanconstant .inwardlydirected current; tjIo avoid, .this'a .fine's hopper 84, either furnishedwith the machine; or provided by the user,. is, attached. toothe, members .2. and. 4.6. and.

is so. constructed...that.. it, tapersfrom the...la rge area.,enclos ed bythesaid member .to a small opening .8.5.iust sufli.cientlydarg accommodate the discharge of the material. passingthat point. Similarly. to ..st o an' excess inflow of air throughithe operrin siill 'and.3l, and.. a't, the same timehto permit-theatres discharge .of material throughthegsame fieidbleucurtains A9, f rubher. or. othenmateriaL'. arepreferablyhung.within them asY shown in. 3, It .WilLbe noted thatginlifiigs. 5

ingtscreen bodymis formed by theamembers, of the enclosure and-ametallic angles mounted on ,thensideeplates ,of thegmachine 1except-,- -in the thel-rubber: skirt/plate =45 forms thenotheriside.

The side plateiitself could have been :usedto form=- and a the-o pen-. mes-between the outside enclosureandthe vibrate 2,se2;2t*au as through the discharge"openingsiill and 3|,

one side of the opening all the way around but due to the fact that at various places on the sideplates there are protuberances of various kinds, including bolt heads, that would require'the enclosure to bespaced farther from the screen body in order to maintain the properand safe operating clearances for the vibrating body, it-

is preferable to extend the sideplates outwardly beyond any such interference by means of the angles shown or by bending the plate itself outwardly. This latter construction is not shown.

Furthermore, to control the amount of air entering through the openings around. the sideopenings 45, 4 l and 44; is drawn into the plenum chamberflF"through' 'the back plate 41 ofthe screen body, Which 'b'ack plate perforatedfor' 'Ifhefplenum chaiiibr'jtvhich has been de. scribed,1is provided for thepurpose Of'regulatihg the velocity"and'distribution of' air removal, and Y its location maybe varied fromthat'shown, the location and constructionjthereof being deter mined by .fcdrlsiderationssucl'ras the'IpOint at 3 J which it isflll'lojs t feasible to'remove the air. Moreover, it*- is I10l7 essential "that a plenum lates, the construction showninFigs. 8 and 9 may be used. In these figures bars of rigid material or of flexible material such as rubber are bolted to the angles 50, 5|, 53 and 54 so that they may allow the full opening between the vibrating body and the enclosure as shown or they may be turned over so that the outward edge projectsbeyond the end of the angles and further restricts the openings 39', ll and 4 4' through which the air passes to enter the body. This restricted opening is shown by the dotted lines.

Fig. 8 also illustrates a modified form of construction as applied to the plenum chamber. In

some cases, as will bebrought out later, this plenum chamber is not used and in that case the backplate of this chamber will not be in the position shown in Fig. abut the extension mem bore 33 shown in Fig. 4 will beeliminated and the backplate brought into the position shownby 34" of Fig. 8 and bolted directly to the uprights l5.

In general, the structure above described coni sists of a stationary box-like enclosurecomplete 1y surrounding the vibrating screen body, except f bottom or thefscrenbodytotlie" center of'the} for an area, on'either side of the screen body,

approximately equal to, and completely expos ing, the areaof the side plate. The en'closure is provided with the necessary openings 23, 30, 3|

and 85 of Fig; 3 to deliver to and discharge from the "screensurfaces the material to be treated and these openings together with the restrici sed passageways 30, Ml, and 44 of Figs. 5and 6 are theonly oints of communication between the interior of the screen'body andthe atmosphere.

In addition to the openings abovedescribed leading" to' the atmosphere, there are various; openings in 'the interior of themachine between various parts where it is desirable to control the passage of the air. For example, in Fig. lit will be seen that as the material passes from the feed opening 23 onto the feed plate of the screen it is subjected to the direct suctionfrom the plenum chamber and if the opening was unrestricted this suction might draw larger particles than desired j frorn the material into the air stream, :In order to eliminate this possibility an additional seal, 48, is fastened to the cover plate angle 36. Ina modified form thissame seal is,

shownjas 4850f Fig. 7. In Fig. 4 the seal is attached to the cover plate angle andis notdistravels or shifts enough to touch it in its cyclic motion the member will give or deform easily and not cause any damage to the machine itself.

Such air that is drawn into the screen body,

chamber be used, and if such'fa chamberis not used, air removal may be accomplished through the discharge "plate,; through the lines hopper which s, usually 'provided fat the bottombf the screenforfthrough thefsi'de plate 'of' the screen body. In the latter -case, an unperforated back" plate wouldfbe used an the screen body instead I of the p erforated plate41.

e. ai fir ma' e ls ste w has been 1 scribed is designed primarily to dampen the dust j in the materialwhich is being screened, and to;

avoid discharge such dust 'into ithe atmosphere about the screen. i Accordingly; air" fromthe space surrounding thescre'en is drawn into'the passing downwardly through the material bein 1' 1' screened from "the top oi 'the screen body and passing upwardly through such :material rromthe screen, as indicatedby the arrows in Fi'glG. This air is drawn' iiito: the plenum chamber through properly proportioned holesflin the screen body" back, plate "41 and, "together with such air as enters the plenum chamber directly through th openings 39, 42 and '43, isdrawhfrom the plenum chamber by me nstr an "aincolleeting System5 'adapted'to be connected to theconduit'3l. The

velocity of the'air within the screen body may be controlled by varying the sizeof the openingsat; the;poirits' l0,"4l and, andinsuch a manner as to' i'a tne dust? 11.58., keep the dust within the screen may Itwill 'ehetedthat during the gy' ator'y movemerit of the screenbod'y, theopenings 39, 40 and AI are not varied in size, since the portions of the enclosure adjacent these openings are arallel with the side plates of thescreen body. This permits the-velocity "of the hair to remainsuostantially uniform throug hout the screening operations, an important consideration, sincejpro an undesirableswirlirlgof the dust.

nounced variations in; the air'velocity may cause I l, be further noted" that since the sides of the air seal rram or enclosur are g cess to the screen cloth tensioning bolts, seen in Fig. 2, maybe had "forfadjustment and other p p ses It is th of and means for controlling dust in the screening of dust-laden; materials, which overcome all of the disadvantages to which reference has hereinbefore been; made. Sincethe air seal or en:

closure is mounted directly onthe stationary base frame of the screen, it is not subjected to the vibratory or gyratory action of the screen body, so

that the cover plates may be made as thin as desirable without causing flexing thereof, and without imposing any burden. on the bearings. Moreover, it is not necessary, in order to make the cover plates dust-tight, to employ an excessive number of bolts or other cover-securing devices,

eal that iohave provided a method thescreensthrough the openings 30 and-3|, may

o thatrthe wo 'J-ei removinaandirepl c e the covemplatesiisi-reduced to; a-minimum: a Further-1. more-,vitis not necessary :to provide flexible .con-

nections whichare; d-ifiicultr-to make dustrtight,

at the fieediand dischargerp'oints-ofithescreen body for .the removal of thezdust,iandtarigidrconduitfor the airexhaust 'suchias 31, maybe directly, connected-to the-air seaLframei-by a dust-tight. connectionr. 'since-zthe air-.sea1--.-framev is station? airy, the :chutes- (not shown), which; areiusuallyi, proyided ior .carryinguther sized material, from 1 pivetallyisecured .to the frame ,of the air seal -eme gev closure and are provided with hook ends 6|, which arehadapted -.t 0 overlie ,thencover,plates andv handles or: fin errpieces 62, Whereby the hooks are swungirelatiyelnto the-cover plates s t i g It -is, te-, beunderstood that itheiform of my-invention,, herewith shQWn-andideScribed, is to be taken-1 as preferred example-of the same,- and that: war-ions richanges i in, the s anefsize anda r-. ran e nent of! parts .mayigbe resorted v,to, Lwithout r depar-tingrfromitherspiri t of my invention or h .13 scopeof the subioined claims-m; y

Having thussdescribedvmy, nventi on; I plaim; i, 1. In, ascreeningtmechanism; aehase a screens. membrane-mounted; en saidabase rfor. reciprocatory movements an enclosure -ior :saidesoreen-memben,

comprising ra casing structure surroundingithe screen and-.anoun tedaon said.base-independently, T of the-screen rmountingi.andu-spa.ced:.from.,th .s screent-rsaidscasingstructure c mprisineta skele-s 4 toneiname rmade-ouip mi and :uprig-hts proieetingneo fromithebaserandi longitudinal members conne.ct ingithetuppen andi lower ends of itheeupnightsrtoe h nend wallsnforthe Leasing 1 structure haying, i discharge: gepeni-ngs therein andna coven and n; bottom wa11 .-completingJane, casingistmcture; the. space between the uprights and longitudinahconau. necting imemberswat, the, sides. of; the, casing ist uc-e u ice s tntineeionsated inesrandtan Ql m-w let ion the casingzthroughwhich suctien maysbe z in applied]. m I

2-. a"screeningqrnechanismn a.;base;- a =p1u-. T311135! 0f uperposedfiscreensi,connected itogethen f by side plates \moi-mtem onsaidrbasenfer lrecipro catoryun evemente an iencl-osure-iforn-saidscreens comprising-1a casinsestructure surroundin the;

the air .both ,flbQYeand below the. screen Mr t 5 3. In a screening irnechanism,in.hase,..a.. nlu

ralityior superposed. screensconnected tegether by openings, andmagainststhe sidenplates to direct motement gan enclosure. for, isaidscreens com-.

prisingia casing.structuresurnounding the screens 1 andm ountedton saidbase independently of thew mounting florithe screensi and in spaced relation 1 i to said-screens said casing comprising .end walls,

. side; w-allshand;bottom -andtopgwalls, ;.the .side

wallsweachihaving an enlo ngated opening, therein of an area slightly 'lejssitha n the area oi the screen connecting .piates andnlying ;adj acent thereto, and. v, meansicfpr drawingairthroughsaidopemngs, and i against.thezsidev-plates todirect the air bothabove andbelow theiscreens, said}side plates-beingiprov videdzwith means,fonvarying therspace between said ,,p1ates,;.and casing-.120 varyhthevfiowvof the air as ittpasse siabove and. below the screens. y

4. In a,soreening' mechanismsa ,hase,-;a plu-i mam; superposedsscreens connected together. 1 by s'ide.p1ates. mountedon said basefor reciproca.-. torysmovement, an enclosure ,for. said. screens. compnising.a-casing. structure surrounding the screens-and mounted on' said ,bas'eindependently; of the-mountingQior,the. screens ancLin spaced i relatiomtp {said screeng .said:. casing vcomprising end wailsl "deiwallna'ndbottemiand topiwalls; the side iwal ls'nach having an enlongated openingthereimof an area,s1ightly;less..,than thearea of thevsoreeni connecting platesandlyingadjacent thereto, andimeansrfor drawingiairthrough said, openings, and against thefside. plates .to direct me n ibothiaboyenanqhelow the screens, said; side plates. being proyidectiwith istripswhich. may. .i be projected toward or away from thesides of the casing to vary the flow of air as it passes.

aboveand ibelowthe screens. e

5, ,In ascreeningmechanism, .a.,base, .a screen mounted for reciprocatory movement on said base,

an enclosurerfor .said screen comprising a .casing structure surrounding ;..the soreen andmounted on the. base independently. on the screen mounting. .7

spacedv from one end wall andgbeing provided with. 7 pro perly:v proportioned perforations through which air is drawn from the casing.

6. In aiscreening niechanism,-a base ascreenmember mounted .onsaidibasevfor reciprocatory.

movement,- an enclosure. forisaid screen .member c01nprising,,.a; casing structure surrounding. the i screen. ands-mounted on js'aid-jbase independently T of the screens mountings. ,andnspaced; iirom the screen, .said.=casine including side bottomandtop wailsaandntwo, end walls, lpne. having 1 a .discharge 1 therein for screened ,materiali andwthe ,bpposite endiwalihaving an openingtherein through which air is drawnifromthe interior of the casing,said end. walls heinghinged to. a..portion\o the casing so as to swingrdownwardlyland outwardly from the side..wall's of thercasin-gi to, Y, permitwaccess .to

the screen andthe sidewall-s of the casing being provided with eopeningsnthrough which air ,is drawn into.the;casing.., y

.WALIER1J; BARKSU 

